Centrifugal machine.



G. TER MEER.

GENTRIFUGAL MACHINE.

APPLICATION FILED DEC. 10, 1913.

Patented Apr. 21, 1914.

2 SHEETS-SHEET 2.

y H n U I W? y 10d QE M &

INVENTOR A TTOR/VE Y eus'rav Tim Mann, or-HANOVE GERMANY.

- cEN'rnIFUGAL MACHINES Specification of tettrs' Patent.

Application filed DecemberlO, 1913-.- Serial No. 805,694.

To all whom it may concern:

Be it known that I, GUSTAV TER'MEER, a

- subject of the Emperor ofGermany, and a resident of -Hanover, in theProvince of Hanover, Prussia, Germany, have invented certain new anduseful Improvements/in Centrifugal Machines, of which the follow .ing isa specification.

This invention relates to certain improvements in centrifugal machinesand more particularly to that type adapted for use in thetreatment ofliquids from which a foam may bereadily produced, such for instance assewage or other liquids containing sapo-' naceous ingredients.

My invention resides in the means em-- ployed for preventing theformation offroth by the liquid thrownout from the machine and fromwhich the solid or heavier materials have been separated. Some liquidswhen thrown out over the edge of a part of a machine rotating at highspeed and striking the outer casing with considerable force are brokenup and converted into foam, which interferes with the operation of themachine. In my improved construction I provide an annular, stationary,upwardly inclined wall closely adjacent to the overflow edge anddirectly in'the path of the liquid. Due to the fact that the inclinationof the annular stationary surface is only slightly different from thedirection in which the liquid tends to travel as it leaves theoverflowedge, and due ,to'the fact, that the overflow edge is disposedclosely adjacent to this surface, the transfer of the liquid from one tothe other is accompanied by but slight loss of momentum in the liquid.Due to the upward inclination of the wall,the tendency of the liquid totravel around this annular stationary wall and outwardly toward theperiphery 'is resisted, not only by the consequent upward movement ofthe liquid against gravity but also by the friction wlththe surface overwhich itis traveling. The speed of the liquidwill' thus be reduced tosuch'a degree that when it leaves the upper outer edge of theinclinedwall the tendency through a machine embodying my invention.

- Ifig. 2 is a vertical, central, longitudinal section of a portion o'f'the drum on a somewhat larger scale; and showingcertain featuresdiffering somewhat indetail of construction frornthat shown in Fig. 1;and Fig. 3 is a vert cal section through my improved froth 'preventerdesigned for use with a somewhat different form of drum.

* The machine shown in these drawings embodies variousimportantand novelfeatures,

" Patented Apr;21",'1914.

but in the present application,- I have divided out all clalms to suchfeatureswith the eie lower end suitable driving connections such forinstance asa'pulley 12, whereby the machine may be driven athigh speed.

. Intermediate of its ends the shaft is sup ported in a suitable bearing13, and at its upper end it carries a head 14 secured thereto in anysuitable manner. head has a central aperture with a conical seatreceiving the conical upper, end of the shaft and locked in upper end ofthe shaft. The head forms the inner or centrallcore of the separationcham- As shownthe place by a nut on the ber or drum, and is encircled bythe peripheral w.all 15 of the drum, which latter is spaced from thehead the required distance to leave the annular separation chamber. Thehead adjacent its lower end has integral therewith or rigidly securedthereto an an-. nular wall 16 constltutin the bottom of theseparationchamber or ing a. peripheral-face contacting with the innersurface of the peripheral wall. At the upper'end of the peripheral wall15'is a top wall or lid 17 held r1 id in "respect to the bottom 16 inany suita stance by vertically extending posts 18.

The top wall or lid 17 has a large-central opening, through whichextends the supply pipe 19 for the materialto be treated. At the lowerend of the supply pipe are spaced guiding lates 20 and 21 extendingoutwardly over t e head 14 and carrying at their peripheries twocylindrical spaced rum, and presentle manner, as for inplates or walls22 and 23 which latter terminate at their lower ends adjacent to thebottom wall 16. Thus the'material to be treated and which enters throughthe supply pipe 19 is delivered to the drum closely adjacent the bottomof the latter and in a thin annular stream, but ordinarily not untilafter the drum orseparation chamber including the peripheral wall andthe bottom and top walls 16 and 17, have reached the desired high speedof rotation. As the mixed liquid and solid material is admitted thesolid or heavier material will be thrown by centrifugal force againstthe wall 15,

while the lighter or liquid portions will oollect as an inner or morecentrally disposed layer. As the material continues to flow into thedrum and the latter continues to rotate at high speed, the drum willeventually become filled to such an extent that for each additionalquantity of material entering the machine a corresponding amount willflow over the upper, inner edge of the top wall 17. As this edge isnearer the center of rotation than is the peripheral wall 15, it isevident that it will be the lighter or more liquid portions which willoverflow, and that the heavier or more solid materials will remain inthe drum. Thus there will be a continuous circulation through themachine, but the heavier particles will be retained. The proper rate offlow of the fluid through the machine determines the capacity of themachine, and is regulated in accordance with the composition of thematerial to be operatedupon and by the completeness with which it isdesired to separate the solids from the liquid. The slower thecirculation'the longer the material will stay in the machine and thelonger it will be exposed to centrifugal force, thus more solidsubstance will be deposited and the liquid thrown out over the edge ofthe top wall. will be purer or clearer. The solid material separated bycentrifugal force, will settle on the outer or peripheral wall and theresulting layer of the solid material will grow by degrees until thedesired thickness has been reached at which time the supply will be shutoff. The machine will now contain an outer layer of compact solidmaterial and an inner layer of liquid or semiliquid material. Theinnermost layer which extends to the overflow edge may be comparativelyclear liquid and ejectin the solidmaterial at this time would resu t ina simultaneous discharge of the liquid and semiliquid portions remainingin the drum. In order to remove this liquid and the semiliquid portionsbefore ejecting thesolid or well-dried material I provide a siphon pipe24 mounted in the top or frame 25 of the machine and extending into thedrum with a pivotal support so that its lower end may be swung inwardlyto inoperative position adjacent the top of the plate 20, or may beswung outwardly about a vertical axis to the point illustrated inFig. 1. The open end of the pipe when in the latter position willproject into the liquid or semi-liquid layers in the drum and due to thehigh speed of rotation of the latter this portion will be forced intoand up the siphon pipe and will be ejected from the machine through adis charge pipe 26. After the withdrawal of the liquid and semi-liquidportions from the ders 27, each containing a piston 28, the piston rod29 of which extends down through a stufling box at the lower end of thecylinder. All of the piston rods at their lower ends are connected tothe lower end of the peripheral wall 15 by means of an annular plate 30or a plurality of separate arms disposed below the bottom 16 of thedrum. Extending lengthwise through the main shaft 10 are two liquidpassages 31 and 32,

one of which is connected by suitable branch passages to the upper endsof all of the cylinders while the other is-connectcd by suitable branchpassages to the lower ends of all of the cylinders. Adjacent its lowerend the shaft is provided with a sleeve 33 having two annular grooves orpassages on the inner surface, one of which communicates with onepassage of the shaft and the other communieates with the other passage.The sleeve is nonrotatable and has two fluid supply pipes 34 and 35,connected thereto, one leading to each internal groove or passage, thusfluid may be delivered to the lower ends of all of the cylinders, fromthe supply pipe 35, or maybe delivered through the supply pipe 34 to theupper ends of all of the cylinders, irrespective ofthe speed of rotationof the shaft. By controlling the flow of fluid through these supplypipes the pistons may be simultaneously forced upwardly or downwardly intheir respective cylinders, and the peripheral wall 15, will at the sametime be raised or lowered. It will thus be noted that the peripheralwall is raised or lowered by fluid pressure and that its raising orlower ing may be accomplished entirely independently of its rotation.The fluid for effecting the movement may be either liquid or gas- .eousbut is preferably a liquid such for instance 'as oil delivered from asuitable source .may before d up against the top wall with 'anydesiredegreesof pressure. This pressjug of the peripheral walland the :top walltogether by means of fluid pressure is an important feature of my'invention, inasmuch as it permits the effective sealing of the jointbetween the lid and the peripheral wall. As shown in Fig. 1 and moreclearly in Fig. 2, the top wall is of larger diameter than theperipheral wall and presents on its under surface a seat-adapted toreceive a gasket 36 against which the peripheral wall may be pressedbythe application of fluid,

pressure to the under sides of the pistons 28, This pressure will ofcoursebe proportioned to the centrifugal force exerted on the ma %terialin'the drum and the resulting tendency of the latter to escape throughthe oint.

With the bottom wall and the peripheral wall axially movable so as toeffect a discharge of the'materialI secure a tight joint between thesewalls preferablyby means of a packing the operative pressure of which isdirectly dependent upon centrifugal force. This may be in addition toasuitable gasket to which pressure is applied by the axial' movement ofthe casing. As shown particularly. in Fig 2 the. peripheral -wa llpresents a shoulder 37 ad acent its lower end upon which is seatedagasket 38, the shoulder and gasket being so positioned that when theperipheral wall isforced upwardly tobring its upper edge against thegasket 36, the gasket 38 will. be pressed against the under surface ofthebottom 16.

The bottom wall on its peripheral edge is preferably provided with anannular recess w thin which is placed a. packing engaging with. theinner surface of the peripheral wall. Thispacking is so'constructed andso mounted that it is acted upon by centrifugal force and 1s pressedoutwardly against the peripheral wall with a pressure directly de-'pendent upon centrifugal force. This packmg may be lthelf of elasticmaterial or of metal or both may be employedif desired.

action of centrifugal force .the packing should not be a single ring,but. should be made of sections or should be in the form'of d1v1dedrings or s'pirals. As shown in Fig. 2 the bottom wall at its peripherycarries two superposed packing rings-39, 39. The packing or the looseweight in the rear thereofhas such specific weight that when the machineis in operation the packing will 'be' pressed against the peripheralwall more firmly than is the material within the drum, so that thelatter can not escape past the Pa I In the treatment of certain classesof material in my machine the throwing" of the liquid against theperipheral wall or casing tion of undesirable amount of froth. This isparticularly true in treating sewage, in'

which considerable quantities of soap or Toap compounds may be insolution in the iqul My-present invention resides solely in the meansfor preventing this "froth formationand includes an annular upwardly.inclined stationary wall over which liquid must pass before escaping.The frictional resistance encountered, the upward direction of themovementmf the liquid and the thinning out of the liquid as it coversthe larger areatoward the periphery, all retard the flow of the liquid,so that when the. liquid escapes from the upper free edge of thisstationary wall it has lost to a large extent its velocity and may dropinto .thereceiving chamber or conduit without the formation of froth toany objectionable extent.

In Fig. 1 I have shown the top wall 17 provided'with a lip 42 from thefree edge of which the liquid is discharged during the operation of themachine The outer stationary casing 43 of the machine carries an annularinclined wall 44, the lower inner edge of which is slightly below thefree edge of the lip 42. Around the outer edge of the which it may flowthrough the contact 46.

It will be noted that this wall 44 is stato travel around the wall andthat the ,ve-"

locity of the liquid will have been very largely overcome by" the timethe liquid .flows over the'outer edge into' the trough. Thus theliability of the formation of froth is largely if not entirelyeliminated. In Fig. 21 have shown a'slightly modified construction inwhich the upper inner edge of the lid is bent outwardly to form the lip42 and the trough 45 is curved in cross-section, but operates insubstantially the'same manner as the construction shown in Fig. 1. Thesame principal of reventing froth for I mation may be embo led invarious other forms of centrifugal machines: In Fig. 5, I have shown'aportion of'a machine in which the peripheral wall 47 is either permeableor perforated sothat the vliquid'may pass direct-1y therethrough whilethe solid material will remain within the drum. In this construction Iprovide an outer wall 48.

rigid with the ermeableor perforated wall and closely jacent thereto sothat the liquid in being thrown out will only travel a very slightdistance'before striking this outer imper'forate wall. No. froth will beformed .at this point as the two walls are traveling together. Theliquid will flow down the inner surface of the wzill ls/and ffl) thebase of the machine.

will then be thrown out on to an annular inclined wall 44 correspondingexactly with the inclined wall 44 shown in Fig. 2. This wall leads to atrough 45 from which the liquid may be discharged. The effect of thisannular inclined wall is as previously indicated, to reduce the velocityof the liquid without material froth formation.

As previously indicated the material is discharged from the drum bylowering the peripheral wall and permitting material to be thrown out bycentrifugal action. The casing 43 is preferably spaced from theperipheral wall a short distance so that the material may strike thiscasing and drop down into an annular channel 49 adjacent An inner wall50 may be carried by the casing 43; concentric therewith, so as toprevent matei ial from falling into the space beneath the drum and thusinterfere with the downward movement of the wall 15. Various mechanismsmay be employed for removing the material from the trough 49 butpreferably I provide a scraper 51 connected to a worm wheel 53,concentric with the shaft but unattached thereto. The connection may bea plate 54 which will prevent any material from dropping on to the wormwheel. A worm 55 driven in any suitable manner may mesh with the wormwheel and effect the slow rotation of-the latter and the scraper so asto deliver the dried material to an outlet conduit 56. This conduit mayhave a slide valve 57 or any other suit-able means for controlling it.

In the operation of my improved machine the successive steps preferablytake place substantially as follows:. Suitable power is applied to theshaft 10 to rotate the latter at very high speed, and the inlet valve 58in the supply conduit is opened to permit the admission of the mixedliquid and solid material to be treated. As previously indicated thissolid material accumulates against the inner surface of the wall 15while the. liquid overflows from the lip 42 and eventually reaches thedischarge conduit 46 while froth is prevented by the plate or. wall 44.When the solid material has accumulated to the desired extent the inletvalve 58 is closed and' the siphon pipe 24 is rotated about a verticalaxis to substantially the position shown in Fig. 1, so that the liquidremaining in the drum and which has not been thrown out from the lip 42will be drawn off. "This liquid which may be comparatively rich in solidmaterialmay he returned to the original source of-supply to be retreatedrat-her than disposed of with the liquid flowing out through the outlet46. The pressure below the pistons 48 is now released andpressure isapplied to the upper thrown out by centrifugal rce against thestationary casing 43 and dropped down into the trough 49 from which itis removed by the scraper 51. The peripheral wall is then returned tothe position shown in the drawing, the siphon pipe is moved toinoperative position and a fresh supply of material to be treated isadmitted by opening of the inlet valve 58. It is of course evident thatthe timing and controlling of these operations may be'done entirely byhand, but I preferably accomplish them automatically. In my co-pendingapplication Serial No. 805,693, filed December 10,1913,I haveillustrated a mechanism which is particularly useful in controlling amachine of the character shown in the present application. The inletvalve 58 may be operated by a piston mounted in a cylinder 59 and thesiphon operative positions by the reciprocation of a piston in acylinder 60. The mechanism illustrated in my co-pending applicationabove referred to may operate to control the flow of liquid to and fromthe cylinders 27, 59 and 60 so that the successive operations may beperformed in the desired sequence after the desired amount of solidmaterial has accumulated. The length of time required for this toaccumulate may be automatically controlled as disclosed in my copendingapplication above referred to or may be accomplished manually.

Having thus described my invention, what I claim as new and desire toprotect by Letters Patent, is:

1. A centrifugal machine for separating ,mixtures including foam formingliquids, comprising a drum adapted to receive a stream of said mixtureand having a peripheral wall against which the heavier or solid portionsof said mixture may collect and be retained within said drum when saiddrum is rotated at high speed, and an overflow edge over which the foamforming liquid may be thrown out at high speed, an annular troughreceiving said liquid and a stationary annular ascending wall receivingsaid liquid directly from said overflow edge, and delivering it to saidtrough at such reduced speed that it will enter said trough without foamformation.

2. A centrifugal machine for separating mixtures including foam formingliquids comprising a drum adapted to be rotated at high speed and havinga delivery edge from which the foam forming liquid may be delivered bycentrifugal force at high speed, an annular trough encircling said drum,and including inner and outer peripheral walls and a stationary annularupwardly and outwardly inclined wall supported by the inner peripheralwall of said trough and extendsides of the pistons to force the casingdownwardly axially. The solid material will be pipe 24 may be moved tooperative and in-- livery edge without shock and delivering it to saidtrough at such reduced speed as will prevent the formation of foam assaid liquid leaves said wall in said trough.

3. A centrifugal machine for separating mixtures including foam formingliquids comprising a drum adapted to retain the heavier or solidportions of said mixture,

and having an upwardly and outwardly inclined annular overflow lip orflange and a stationary upwardly and outwardly inclined annular wallclosely adjacent to said lip or flange, the surface of said Wall beingat a very slight angle to the direction of flow of said liquid as itleaves said lip or flange and serving to receive said liquid andgradually slow down the movement of the latter and permit it to flowfrom said wall substantially without foam formation.

4. A centrifugal machine for separatin mixtures including foam formingliquids 7 comprising a drum adapted to retain the heavier or solidportions of said mixture, and having an overflow edge and a stationaryupwardly and outwardly inclined annular wall closely adjacent to saidoverflow edge, the surface of said wall being at a very slight angle tothe direction of flow of said liquids as it leaves said overflow edgeand serving to receive said liquid and gradually slow down the movementof the latter and permit it to flow from said wall substantially withoutfoam formation.

Signed at Hanover, Germany this twentysixth day of November, A. D. 1913.

GUSTAV TER MEER.

